Abstract: A photoelectric conversion device in which an increase in driving voltage is inhibited is provided. The photoelectric conversion device includes a first electrode, a second electrode, and an organic compound layer; the organic compound layer is positioned between the first electrode and the second electrode; the organic compound layer includes a first layer; a structure body including projections is included between the first layer and the second electrode; and the structure body contains a first organic compound.

Abstract: The field-effect mobility and reliability of a transistor including an oxide semiconductor film are improved. A semiconductor layer of a transistor is formed using a composite oxide semiconductor in which a first region and a second region are mixed. The first region includes a plurality of first clusters containing one or more of indium, zinc, and oxygen as a main component. The second region includes a plurality of second clusters containing one or more of indium, an element M (M represents Al, Ga, Y, or Sn), zinc, and oxygen. The first region includes a portion in which the plurality of first clusters are connected to each other. The second region includes a portion in which the plurality of second clusters are connected to each other.

Abstract: A semiconductor device with favorable electrical characteristics is provided. A highly reliable semiconductor device is provided. A semiconductor device with stable electrical characteristics is provided. A semiconductor device includes a first insulating layer, a second insulating layer, a semiconductor layer, and a first conductive layer. The semiconductor layer, the second insulating layer, and the first conductive layer are stacked in this order over the first insulating layer. The second insulating layer has a stacked-layer structure in which a first insulating film, a second insulating film, and a third insulating film are stacked in this order. The first insulating film, the second insulating film, and the third insulating film each contain an oxide. The first insulating film includes a portion in contact with the semiconductor layer. The semiconductor layer contains indium, gallium, and oxygen and includes a region with an indium content percentage higher than a gallium content percentage.

Abstract: A transistor includes a multilayer film in which an oxide semiconductor film and an oxide film are stacked, a gate electrode, and a gate insulating film. The multilayer film overlaps with the gate electrode with the gate insulating film interposed therebetween. The multilayer film has a shape having a first angle between a bottom surface of the oxide semiconductor film and a side surface of the oxide semiconductor film and a second angle between a bottom surface of the oxide film and a side surface of the oxide film. The first angle is acute and smaller than the second angle. Further, a semiconductor device including such a transistor is manufactured.

Abstract: A semiconductor device comprising an oxide semiconductor film, a gate electrode, a first insulating film, a source electrode, a drain electrode, and a second insulating film is provided. Each of a top surface of the gate electrode, a top surface of the source electrode, and a top surface of the drain electrode comprises a region in contact with the second insulating film. A top surface of the first insulating film comprises a region in contact with the gate electrode and a region in contact with the second insulating film and overlapping with the oxide semiconductor film in a cross-sectional view of the oxide semiconductor film. The oxide semiconductor film comprises a region in contact with the first insulating film and a region in contact with the second insulating film and adjacent to the region in contact with the first insulating film in the cross-sectional view.

Abstract: The transistor includes a first gate electrode, a first insulating film over the first gate electrode, an oxide semiconductor film over the first insulating film, a source electrode over the oxide semiconductor film, a drain electrode over the oxide semiconductor film, a second insulating film over the oxide semiconductor film, the source electrode, and the drain electrode, and a second gate electrode over the second insulating film. The first insulating film includes a first opening. A connection electrode electrically connected to the first gate electrode through the first opening is formed over the first insulating film. The second insulating film includes a second opening that reaches the connection electrode. The second gate electrode includes an oxide conductive film and a metal film over the oxide conductive film. The connection electrode and the second gate electrode are electrically connected to each other through the metal film.

Abstract: A transistor includes a multilayer film in which an oxide semiconductor film and an oxide film are stacked, a gate electrode, and a gate insulating film. The multilayer film overlaps with the gate electrode with the gate insulating film interposed therebetween. The multilayer film has a shape having a first angle between a bottom surface of the oxide semiconductor film and a side surface of the oxide semiconductor film and a second angle between a bottom surface of the oxide film and a side surface of the oxide film. The first angle is acute and smaller than the second angle. Further, a semiconductor device including such a transistor is manufactured.

Abstract: A semiconductor device with favorable electrical characteristics, a semiconductor device with stable electrical characteristics, or a highly reliable semiconductor device or display device is provided. A first insulating layer and a first conductive layer are stacked over a first region of a first metal oxide layer. A first layer is formed in contact with a second metal oxide layer and a second region of the first metal oxide layer that is not overlapped by the first insulating layer. Heat treatment is performed to lower the resistance of the second region and the second metal oxide layer. A second insulating layer is formed. A second conductive layer electrically connected to the second region is formed over the second insulating layer. Here, the first layer is formed to contain at least one of aluminum, titanium, tantalum, and tungsten.

Abstract: A semiconductor device is fabricated by a method including the following steps: a first step of forming a semiconductor film containing a metal oxide over an insulating layer; a second step of forming a conductive film over the semiconductor film; a third step of forming a first resist mask over the conductive film and etching the conductive film to form a first conductive layer and to expose a top surface of the semiconductor film that is not covered with the first conductive layer; and a fourth step of forming a second resist mask that covers a top surface and a side surface of the first conductive layer and part of the top surface of the semiconductor film and etching the semiconductor film to form a semiconductor layer and to expose a top surface of the insulating layer that is not covered with the semiconductor layer.

Abstract: The transistor includes a first gate electrode, a first insulating film over the first gate electrode, an oxide semiconductor film over the first insulating film, a source electrode over the oxide semiconductor film, a drain electrode over the oxide semiconductor film, a second insulating film over the oxide semiconductor film, the source electrode, and the drain electrode, and a second gate electrode over the second insulating film. The first insulating film includes a first opening. A connection electrode electrically connected to the first gate electrode through the first opening is formed over the first insulating film. The second insulating film includes a second opening that reaches the connection electrode. The second gate electrode includes an oxide conductive film and a metal film over the oxide conductive film. The connection electrode and the second gate electrode are electrically connected to each other through the metal film.

Abstract: A semiconductor device with favorable electrical characteristics is provided. A highly reliable semiconductor device is provided. A semiconductor device with stable electrical characteristics is provided. A semiconductor device includes a first insulating layer, a second insulating layer, a semiconductor layer, and a first conductive layer. The semiconductor layer, the second insulating layer, and the first conductive layer are stacked in this order over the first insulating layer. The second insulating layer has a stacked-layer structure in which a first insulating film, a second insulating film, and a third insulating film are stacked in this order. The first insulating film, the second insulating film, and the third insulating film each contain an oxide. The first insulating film includes a portion in contact with the semiconductor layer. The semiconductor layer contains indium, gallium, and oxygen and includes a region with an indium content percentage higher than a gallium content percentage.

Abstract: A semiconductor device with favorable electrical characteristics is provided. A semiconductor device with stable electrical characteristics is provided. A highly reliable semiconductor device is provided. A semiconductor layer is formed, a gate insulating layer is formed over the semiconductor layer, a metal oxide layer is formed over the gate insulating layer, and a gate electrode which overlaps with part of the semiconductor layer is formed over the metal oxide layer. Then, a first element is supplied through the metal oxide layer and the gate insulating layer to a region of the semiconductor layer that does not overlap with the gate electrode. Examples of the first element include phosphorus, boron, magnesium, aluminum, and silicon. The metal oxide layer may be processed after the first element is supplied to the semiconductor layer.

Abstract: A display device includes a liquid crystal element, a transistor, a scan line, and a signal line. The liquid crystal element includes a pixel electrode, a liquid crystal layer, and a common electrode. The scan line and the signal line are each electrically connected to the transistor. The scan line and the signal line each include a metal layer. The transistor is electrically connected to the pixel electrode. A semiconductor layer of the transistor includes a stack of a first metal oxide layer and a second metal oxide layer. The first metal oxide layer includes a region with lower crystallinity than the second metal oxide layer. The transistor includes a first region connected to the pixel electrode. The pixel electrode, the common electrode, and the first region are each configured to transmit visible light. Visible light passes through the first region and the liquid crystal element and exits from the display device.

Abstract: To improve field-effect mobility and reliability of a transistor including an oxide semiconductor film. A semiconductor device includes an oxide semiconductor film, a gate electrode, an insulating film over the gate electrode, the oxide semiconductor film over the insulating film, and a pair of electrodes over the oxide semiconductor film. The oxide semiconductor film includes a first oxide semiconductor film and a second oxide semiconductor film over the first oxide semiconductor film. The first oxide semiconductor film and the second oxide semiconductor film, include the same element. The first oxide semiconductor film includes a region having lower crystallinity than the second oxide semiconductor film.

Abstract: A semiconductor device which has favorable electrical characteristics, a method for manufacturing a semiconductor device with high productivity, and a method for manufacturing a semiconductor device with a high yield are provided.

Abstract: A liquid crystal display device with a high aperture ratio is provided. A liquid crystal display device with low power consumption is provided. A display device includes a transistor and a capacitor. The transistor includes a first insulating layer, a first semiconductor layer in contact with the first insulating layer, a second insulating layer in contact with the first semiconductor layer, and a first conductive layer electrically connected to the first semiconductor layer via an opening portion provided in the second insulating layer. The capacitor includes a second conductive layer in contact with the first insulating layer, the second insulating layer in contact with the second conductive layer, and the first conductive layer in contact with the second insulating layer. The second conductive layer includes a composition similar to that of the first semiconductor layer. The first conductive layer and the second conductive layer are configured to transmit visible light.

Abstract: A semiconductor device with favorable electrical characteristics is provided. A semiconductor device having stable electrical characteristics is provided. A highly reliable semiconductor device is provided. The semiconductor device includes a semiconductor layer, a first insulating layer, a second insulating layer, and a conductive layer. The first insulating layer is in contact with part of the top surface of the semiconductor layer, the conductive layer is positioned over the first insulating layer, and the second insulating layer is positioned over the semiconductor layer. The semiconductor layer contains a metal oxide and includes a first region overlapping with the conductive layer and a second region not overlapping with the conductive layer. The second region is in contact with the second insulating layer. The second insulating layer contains oxygen and a first element. The first element is one or more of phosphorus, boron, magnesium, aluminum, and silicon.

Abstract: A semiconductor device which has favorable electrical characteristics is provided. A method for manufacturing a semiconductor device with high productivity is provided. A method for manufacturing a semiconductor device with a high yield is provided.

Abstract: A display device includes a liquid crystal element, a transistor, a scan line, and a signal line. The liquid crystal element includes a pixel electrode, a liquid crystal layer, and a common electrode. The scan line and the signal line are each electrically connected to the transistor. The scan line and the signal line each include a metal layer. The transistor is electrically connected to the pixel electrode. A semiconductor layer of the transistor includes a stack of a first metal oxide layer and a second metal oxide layer. The first metal oxide layer includes a region with lower crystallinity than the second metal oxide layer. The transistor includes a first region connected to the pixel electrode. The pixel electrode, the common electrode, and the first region are each configured to transmit visible light. Visible light passes through the first region and the liquid crystal element and exits from the display device.

Abstract: To improve field-effect mobility and reliability of a transistor including an oxide semiconductor film. A semiconductor device includes an oxide semiconductor film, a gate electrode, an insulating film over the gate electrode, the oxide semiconductor film over the insulating film, and a pair of electrodes over the oxide semiconductor film. The oxide semiconductor film includes a first oxide semiconductor film and a second oxide semiconductor film over the first oxide semiconductor film. The first oxide semiconductor film and the second oxide semiconductor film, include the same element. The first oxide semiconductor film includes a region having lower crystallinity than the second oxide semiconductor film.